Coverage is a very important parameter for describing the vegetation characteristics of land surface.Determining vegetation coverage quickly and exactly is important to research the relationship between vegetation coverage and soil erosion, benefit of soil and water conservation from vegetation coverage，and prediction of soil erosion. The portable photographic instruments for vegetation coverage，which had been developed through several years' practice, was adaptive to determine vegetation coverage by vertical photograph on the flat and sloping field，and could regulate the height from camera to land，enhance the stability of cam- era. Meanwhile, the matching software of portable photographic instruments PCOVER was developed， which could identify the vegetation from photograph automatically and calculate the vegetation coverage accurately. And it had been proved exactly in practice.